/* 
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using Lucene.Net.Support;

namespace Lucene.Net.Analysis
{
    
    /// <summary> Holds a map of String input to String output, to be used
    /// with <see cref="MappingCharFilter" />.
    /// </summary>
    public class NormalizeCharMap
    {
        internal System.Collections.Generic.IDictionary<char, NormalizeCharMap> submap;
        internal System.String normStr;
        internal int diff;
        
        /// <summary>Records a replacement to be applied to the inputs
        /// stream.  Whenever <c>singleMatch</c> occurs in
        /// the input, it will be replaced with
        /// <c>replacement</c>.
        /// 
        /// </summary>
        /// <param name="singleMatch">input String to be replaced
        /// </param>
        /// <param name="replacement">output String
        /// </param>
        public virtual void  Add(System.String singleMatch, System.String replacement)
        {
            NormalizeCharMap currMap = this;
            for (var i = 0; i < singleMatch.Length; i++)
            {
                char c = singleMatch[i];
                if (currMap.submap == null)
                {
                    currMap.submap = new HashMap<char, NormalizeCharMap>(1);
                }
                var map = currMap.submap[c];
                if (map == null)
                {
                    map = new NormalizeCharMap();
                    currMap.submap[c] = map;
                }
                currMap = map;
            }
            if (currMap.normStr != null)
            {
                throw new System.SystemException("MappingCharFilter: there is already a mapping for " + singleMatch);
            }
            currMap.normStr = replacement;
            currMap.diff = singleMatch.Length - replacement.Length;
        }
    }
}